September Phenology

The word for the day is phenology- the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate.  Tana Pulles puts up a poster in her office every month and has volunteered to share her monthly Ozark phenology thoughts with us.

MONARCH BUTTERFLIES

Wikimedia

Every fall, a magical event takes place—the annual Monarch migration to Mexico. In September look for larger numbers of Monarchs on the move or perhaps clustered in a nearby tree. By instinct alone, they migrate distances up to 2000 miles to their wintering grounds in Mexico.

The average peak of the Monarch migration for our 37 degree latitude is the last two weeks of September.

SHOREBIRD MIGRATION
Early September brings the peak of shorebird migration. Shorebirds tend to travel in flocks and are seen near sand and mud flats of standing water, prairie potholes, backwaters and sewage lagoons. Many of them are long range migrants that we see only in the spring on their way to summer breeding locations up north and fall to wintering grounds in Central and South America.

 WATCH FOR FALLING ACORNS Oaks and hickories produce seed crops at irregular intervals. One season may bring bumper quantities of acorns and nuts, while the next season may bring scarce amounts. Red oaks produce their acorns every other year.   Acorns and nuts are of tremendous importance to deer, squirrels, turkeys and other wildlife. Upwards of 100 species of birds and animals include acorns in their diets. Late September observe squirrels busy burying these seeds for their winter food stash.

SOLDIER BEETLES

You don't have to look hard for soldier beetles - these Pennsylvania leatherwings start to cluster on the frost weed, Goldenrod and Thoroughwart (Eupatorium) byt the start of September. Too many can be a nuisance but they are good pollinators and will eat aphids.


COLORS OF FALL
Sassafras, sumac and Virginia creeper begin to show their fall color the last half of September. Look for their brilliant reds.  Above all, don't forget to count the leaves.  Virginia creeper= 5 leaflets; Poison ivy= "leaves of three."  Poison ivy also turns a beautiful shade of red- the same color as your rash if you forget.

Poison Ivy

Virginia creeper- Wikimedia

 HAWK MIGRATION

Broad-winged hawk- Cathy Miller

The later half in September provides the best viewing for hawk migration; one in particular is the Broad-winged Hawk. The best time of day for viewing a band of these migrating raptors is mid-morning on a bright day after a cold front has passed through the area. It is then that you are likely to see hundreds even thousands moving southwards. They are returning to the American tropics where they spend their winters. 

Tiger Salamander- endangerednj.blogspot.com

TIGER SALAMANDERS MOVING
Tiger salamanders spend their days in burrows or under logs, as they are active at night. During autumn rains, adult individuals migrate to fishless ponds where breeding will take place. Courtship and egg-laying occur in the water between February and April. Each female may lay up to 1,000 eggs deposited in small clumps of 18 to 110 eggs. Eggs hatch in a few weeks.

And finally this from Jeff Cantrell in Joplin:

"Common Nighthawks have been migrating through in good numbers, some evenings (20, 40, 60 - 100 birds ) while I have noticed other days I see very few, there seems to be a pulse to the migration. Try to catch them if you get the opportunity. They will be heading to South America as mid-September nears. The “bullbats” have a cool casual flight, followed by some remarkable dives. “Peent” is their rally cry, but sometimes you will hear “beer, beer, beer” almost like science fiction firearm sound effects. "

Stink Bugs

You know you married a naturalist when she carries a little plastic box to bring home bugs from the garden.  Last week there were two stink bug gifts for me to check out.  Worse yet, I was pleased with the gifts.

Sometimes the identification of even commonly seen bugs can be difficult.  There is agreement on the name green stink bug but from there it gets a little contentious.  The green stink bug, Chinavia hilaris, is my first choice based on appearance and the little black spots along the edges.  It is the most commonly encountered stink bug in the US.  ID confirmed

Our Stink Bug- rkipfer

N. viridula  4th Instar- Wikimedia

Another contender is the southern green stink bug, (Nezara viridula), thought to have originated in Ethiopia but it is now found world wide, mainly in tropical and subtropical climes.  They are generalists but seem particularly attracted to the bean family, feeding especially when they are forming fruit or pods.  Early instars can be quite colorful.

C. hilaris Stink Gland- Cotinis

The distinction between these is based on the location and shape of the stink gland on the ventral (underside) of the bug.  It takes dedication and breath-holding to identify this.  Robert Coin has good closeups of C. hilaris which you can view odor free.   A Bugguide closeup shows N. viridula's stink gland orifice. 


Many stink bug species communicate by vibrating a leaf with their own species and sex specific "song" as described in a previous blog.  "When ready to mate N.viridula sound 100Hz vibrations with a tymbal composed of a fused first and second terga that allow bi-directional communication to any Nezara standing on the same plant so they could find each other." Wikipedia
Stink bugs feed by stabbing their needle-like proboscis into the plant, injecting toxins that damage the tissue.  Depending on the site of injury and the degree of physical and chemical damage it may just wound or even kill the plant.  Fortunately, in our garden these were apparently minor wounds.

Euschistus sp.

Euschistus sp. of brown stink bugs are native but that doesn't mean they are more desirable in your garden.  The most common species is the brown stink bug, Euschistus servus.   They are quite prolific, the females producing 18 egg masses, each with 60 eggs on average.  Multiplied by multiple generatons (5/year in Florida), their voracious appetite and strong flying traits and you have real trouble.  Fortunately lots of parasites, pathogens and predators such as our favorite assassin bugs act to keep the numbers in check.

Stink bugs eat our favorite plants, feed other insects and eventually their stored energy passes on to birds and higher predators.  It all works out in the end.

Green stink bug eggs- Chris Barnhart

Garlic Mustard - the First Spice?

Garlic mustard Alliaria petiolata is a major invasive species spreading across the US.  It inhibits growth of tree seedlings and other plants with it allelopathic chemicals.  It was brought to the Western Hemisphere as a familiar herb, and now new research suggests that it was the first known European seasoning from prehistoric times.

A story in PLOS One describes the findings of remnants of garlic mustard in carbonized food products in the bottom of pots dating from 5750 to 6,100 years ago, roughly 4,000 B.C.  As it has little food value, the researchers postulate that it was there for its value as a spice.  Its flavor is, as you might guess, a blend of mustard and garlic.

The description of the research is more easily understood in the article from the BBC.  While we eat the leaves, they postulate that the seeds were ground up and used.

"These deposits contained microscopic traces of plant-based silica, known as phytoliths, which can be used to identify the plants from which they came.  It was these phytoliths that provided the evidence of garlic mustard (Alliaria petiolata) in the carbonized scrapings."

The history of the earliest added flavors to food is indistinct.  Spices may have been used in the Middle East earlier.  Coriander was found in a cave in Israel from around 23,000 B.C., but it hasn't been linked to food preparation or cooking at that time.  So, spice or herb?  According to Wikipedia "Culinary use typically distinguishes herbs as referring to the leafy green parts of a plant (either fresh or dried), from a "spice", a product from another part of the plant (usually dried), including seeds, berries, bark, roots and fruits."

If you aren't familiar with the plant that Barb loves to hate, look up the 2011 blog Cutting the Mustard for more than you want to know.  The only good news is that garlic mustard remains an interesting edible, the young leaves adding a nice bite to a salad or sandwich.  Linda Ellis has suggested that "Its flavor is just a plot to use humans to vicariously carry out it's evil deeds."  Remember, it convinced our forebearers to carry it across the Atlantic.


Details at this link. 
More on edible weeds and plants at ediblewildfood.com.
Thanks to Steve and Amy, the Fishin Magicians for the lead.

Bird's Nest Fungi

Cyathus striatus

Gala Solari sent me this picture.  "Lots of the little fun guys growing in the mulch at the Dewey Short Visitor Center. They are about 1/4" each. You probably already know, but they rely on rain drops to splash the little spores (that look like tiny eggs) out of the"nest."

These little gems are bird's nest fungi, with 5 genera in the Nidulariaceae family.  They are saprophytic, feeding on dead wood and wood chips, helping the gradual transition toward soil.

Wikipedia has extensive technical information but for my purposes, Mushroomexpert.com explains them best.

"These odd and fascinating little fungi look for all the world like tiny birds' nests. The fruiting bodies form little cuplike nests which contain spore-filled eggs. The nests are called "peridia" ("peridium" in the singular), and serve as splash cups; when raindrops strike the nest, the eggs (called "periodoles") are projected into the air, and they latch onto twigs, branches, leaves, and so on. What exactly happens next is not completely clear, but eventually the spores are dispersed from the egg. They then germinate and create mycelia, which eventually hook up with other mycelia and produce more fruiting bodies."*

Gala's picture shows the distinctive fluted bird's nest fungus, Cyathus striatus, which is wide spread in temperate regions.  It is distinguished by hairiness and the grooves in the cup wall, resembling the paper around a cupcake.  In our urban setting it is commonly found in wood mulched garden beds.

A mushroom is the "flowering" part of a fungus, intent on getting its spores up in the air where they can be dispersed by the wind.  Many mushrooms have their spores below an elevated cap where they can fall downward.  In this case, when the egg is propelled into the air by the impact of raindrops, it rips open the funiculus and a tightly wound funicular cord spirals off like a spinning reel in free fall.  The sticky cord clings to a nearby plant or blade of grass, dangling the egg like a tetherball.  Its spores are then hanging up where the wind can carry them away.

*  Mushroomexpert.com has an identification key.
Time lapse video from Cornell shows them emerging.

Bee Assassin

Bee assassin with red milkweed beetle?- Kevin Firth

Kevin Firth sent me this picture of a bee assassin (Apiomerus crassipes) with what may be a red milkweed beetle. Although they are strong fliers, like all assassin bugs they tend to wait and ambush their unsuspecting insect prey, stabbing them with their sucking beak.  They first inject digestive juices into the prey, both paralyzing the victim and starting the digestion process in their victim.  They then suck out the innards like a big milk shake.  Consider this paragraph a part of your neglected weight loss program.

Although bee keepers consider them a major threat, no studies have been done to show that they affect the population.  They usually are found perched on stems and leaves, not the best place to catch a bee.*  Most of the pictures I found on the web show them with other types of insects, mostly bugs harmful to your garden.

That said, they are certainly capable of taking down a bee.  Their hunting strategy is to use a sticky substance, possibly collected plant resin on their strong front legs, which helps them to grab and hold onto bees. They are considered a beneficial insect by all but bee keepers and an occasional gardener who picks one up or otherwise annoys it.

Bee assassin with small bug- Patrick Coin

   Patrick Coin

*  Details at Texas Master Gardeners

Plants Play Defense

Slugs and snails and puppy-dogs' tails, 

That's what little boys are made of.

Snail- an armor coated slug- Wikimedia

Bob Korpella posted an story on slugs, snails and plants on his always interesting Freshare.net website.  Some plants seem to wait to release their predator defenses until there is a threat of attack.

Plants aren't able to run away from predators but have evolved a number of defensive mechanisms to fend off assaults, such as thorns and toxins.  Animals likewise can evolve ways of evading these defenses.  The whole process reminds me of when radar detectors were the rage.  The companies that made them also developed new forms of radar, then sold the heavy footed driver the latest new detector as they developed and even stealthier radar gun.

All lifeforms are deeply involved in the production of energy to reproduce.  Fighting off predators, running away or even producing a toxic chemical diverts precious energy from growth and reproduction.  A plant with a defense chemical that it can make of demand could save some of its energy.

Snails and slugs, which are snails without the hardware covering, leave a trail of slime as they crawl around, a source of fascination to little boys.  These are generalist herbivores, eating a wide variety of plants but they are especially fond of mustard plants so common in nature.  John Orrock of the University of Wisconsin–Madison* has shown that pre-treating mustard plant seedlings or seeds with slime produced plants that were less palatable to the snails and slugs.  The plant seems to hold its chemical defenses in reserve until it senses danger.

C. Barnhart

Plants response to animal stimulus is well known.  They can release volatile chemicals which repel potential predators but can also serve as an attractant to others.**  Black swallowtail butterflies tapping their feet, equipped with olfactory sensors, elicit a chemical response from plants in the carrot family, telling them that it is a plant necessary for their caterpillars growth.  As long as there are a number of plants available, a little caterpillar damage on each plant is tolerable.  Too many cats on just a few plants in your garden may be a problem.

Milkweeds and caterpillars are a good example of this evolutionary battle.  The plant has hairs on the leaves to discourage browsing bugs and their milky latex fluid has cardenolide toxins to help protect it from attack.  The monarch butterfly caterpillar is adapted to the toxin and even absorbs and concentrates it to protect itself from other predators.  Now studies indicate that "more recently evolved milkweed species use less of these preventative strategies, but grow faster than older species, potentially regrowing faster than caterpillars can consume them." Wikipedia

Species that are closely associated like milkweed and monarch are said to be co-evolved.  Monarchs require milkweed for their caterpillars to eat and grow.  They would disappear in a world without milkweed.  They have reached a balance of powers and are unlikely to ever completely destroy each other.  We, on the other hand have developed our own defensive chemicals as well as monoculture crops, capable of wiping out enough milkweed to end the monarch migration.  Now if  we could only learn to use our chemicals sparingly, like some plants can.

*    Eavesdropping Plants Prepare to be Attacked
**  Extensive information is here on Plant Volatiles as a Defense against Insect Herbivores

Like butterflies?  Try planting some fennel and let it grow.  You may be able to watch black swallowtail caterpillars go through their growth stages and develop into the next generation.  They eat a little of your fennel, dill or golden Alexander, birds and other insects eat a few of the caterpillars and the cycle of life goes on right in your backyard.

Black Swallowtail- C. Barnhart

Big Mosquito Year

Many people have commented that it is a bad summer for mosquitoes.  Actually it is a good year for them, a fact blessed by an Associated Press article.  We already knew this but now we know why.

"Two years of drought were followed by incredibly heavy rain this year. During dry spells, mosquito eggs often didn't get wet enough to hatch. This year's rain revived those, along with the normal 2013 batch."

The good news is that the drought gave us two years of fewer mosquitoes.  Cycles like this are the norm - just consider the fluxes in rabbit populations.  Over all, the average population numbers average out.  That probably isn't much comfort while you are busy swatting mosquitoes, or rabbits.

In further bad news, the current climate change will likely produce future bumper mosquito crops.  They thrive in the warm and humid conditions that are predicted for the next few decades.  Like deer and other wild things, they are learning how to get along with humans.  It should come a no surprise that some are developing a genetic resistance to DEET.  Given enough time, they may even learn to love it.  Ouch! And itch.